Improvement in bolt-cutters



J. R! BROWN.

Improvement in Bolt-Cutters.

N0. 131,423. Patented Sep.17,18-72.

UNITE Srn'rns JAMES R. BROWN, OF GAMBRIDGEPORT, MASSACHUSETTS.

IMPROVEMENT IN BOLT-CUTTERS;

Specification forming part of Letters Patent No. 131,423, datedSeptember 17, 1872; antedated September To all whom it may concern:

Be it known that I, JAMES R. BROWN, of Cambridgeport, of the county ofMiddlesex and State of Massachusetts, have made anew and usefulinvention having reference to what are termed Bolt-Gutters; and dohereby declare the same to be fully described in the fol lowingspecification and represented in the accompanying drawing, of which- 7Figure 1 is a front elevation, and Fig. 2 a longitudinal and verticalsection, of my improved bolt-cutter, which, in the main,is analogous tothat for which Letters Patent No. 107 ,438, dated September 20, 1870,were granted to me, and also to that described in an application for apatent filed by me in the Patent Office on October 12, 1870, and allowedon December 24, 1870.

Each of the said bolt-cutters last mentioned had its movablecutter-carri er constructed with two racks or series of teeth, disposedon opposite sides of it, and engaging with sectoral or areal ranges ofteeth projecting from two levers pivoted to the stationary cutter heador plates projecting therefrom These teeth being liable to become brokenby the great strain and wear to which they necessarily are subjectedwhile the implement is. in use, I have sought to dispense with them andto employ in their stead other devices, not only of adifferentcharacter, but operating in a different manner, and with far greatereffect, aswell as with little or no liability of breakage, comparativelyspeaking.

In the drawing, A denotes the cutter-head or yoke, provided with thestationary cutter a, and a movable or sliding chisel, 'b, the latterbeing soeketed into a carrier, B, so as to be capable of being movedendwise therein by means of an adjusting-screw, O, screwed into thecarrier, all being arranged in manner as represented. The movable cutteris grooved in its side lengthwise, as seen at O, to receive a stud, cl,projecting from the yoke, the groove and stud serving to prevent thecutter from revolving. To the yoke or cuttenhead A two levers, D D, arepivoted, their fulcrums or j ointpins being shown at e e. The saidlevers D D are formed with shoulders or abutments ff, and thecutter-carrier B is also provided with shoulders or abutments g g, allbeing arranged as represented. Between the shoulders of the carrier Band those of the levers D D, and also between the carrier and the twolevers, are two toggles, E E, each of which is hinged or pivoted at oneend to the carrier and at the other to one of the levers. When thelevers are about in'parallelism the abutments ff, at their inner edgesby contact with the cuttercarrier, serve as stops to arrest the furtherinward motion of the levers, and as a consequence the advance of themovable cutter toward the stationary cutter. On taking hold of thelevers and moving them apart the cutter-carrier B will be retracted bythe toggles. So, when the levers are moved toward each other, thetoggles will advance the said carrier, the force of the propulsionconstantly increasing as the advance is made.

Fromthe above it will be seen that thetoggles have one importantadvantage over toothed racks and sectoral gears, which, while inoperation, advance the cutter-carrier equal distances, with equal arcsof movement of the levers and with a constant force; whereas with thetoggles such is not the case, as with them during the movements of thelevers toward each other the advance of the cutter-carrier constantlydecreases, and the force of propulsion as constantly increases with nodanger of breakage of any part, as the abutments or shoulders of thelevers and the cutter-carrier screw it from the carrier the movablecutter may be drawn out of the carrier forbein g sharpened, or for anyother purpose.

I herein make no claim, in a boltcutter, to i the toothed stock of themovable cutter and toothed segment-levers arranged as shown in theUnited States Patent No. 65,391. Nor do I claim the combination ofknives, levers, screw, frame, and top and bottom plates, constructed andarranged in manner and to operate as described in such patent or in thereissue thereof, dated March 14, 1871. I make no claim to anything shownor described in the United States Patent No. 105,629.

I clain1 1. My improved bolt-cutter, as having the toggles E E, thelevers D D, the cutter-carrier B, cutter b, and the cutter-head A,constructed, arranged, and combined in manner as shown and described.

2. I claim the adjusting-screw O, and the movable cutter or chisel b, asmade and applied together and to the cutter-carriers, as set forth, thechisel under such application of it being provided with the groove 0,open at its front end to receive the stud d from the carrier, all beingas specified.

- JAMES B. BROWN. Witnesses:

It. H. EDDY, J. It. SNOW.

